Centrifugal Casting vs. Bar Stock: Which is Better for Hollow Parts?

When sourcing cylindrical parts such as sleeves, bushings, tubes, or rings, engineers and procurement directors traditionally default to bar stock. While bar stock is familiar, it’s often not the most cost-effective or efficient solution for parts with a hollow interior. 

At Delta Centrifugal®, we specialize in centrifugal castings—an alternative manufacturing method designed specifically for hollow cylindrical components. The main advantage is simple: the material already has the hole in it. Instead of removing metal from solid bar stock through trepanning or deep-hole drilling, we cast your parts directly to the exact tube size required. 

Using bar stock for hollow parts comes with hidden costs and inefficiencies: 

• Material Waste: Trepanning solid bars results in significant metal removal, often wasting 30% to 60% of the purchased alloy. This becomes especially costly with large components or specialty metals like duplex, cobalt, or nickel-based alloys.
• Machining Costs: Trepanning and drilling takes considerable machine hours and accelerates tool wear, adding to labor cost, tool replacement, and maintenance expenses.
• Extended Lead Times: Additional machining steps lead to longer production cycles, impacting schedules and delaying deliveries.

How Centrifugal Casting Solves These Problems 

Centrifugal casting eliminates the inefficiencies of bar stock by casting molten metal into a rotating mold, forming a hollow shape naturally: 

• Minimal Material Waste: The hollow interior is cast in place, drastically reducing excess metal. 
• Lower Machining Requirements: With the part already cast close to its final shape, machining is minimized to finishing operations, significantly reducing tooling costs and labor time. 
• Enhanced Material Properties: Centrifugal force moves impurities to the inner surface, easily removed during final machining, leaving a denser, more uniform grain structure that boosts part strength and durability.

Common Applications and Industries Benefiting from Centrifugal Casting 

Centrifugal casting particularly excels in these scenarios: 

• Large-diameter hollow components (over 8 inches) 
• High-value alloys (stainless steels, duplex alloys, Inconel, etc.) 
• Parts produced frequently, where savings in material and machining quickly add up 
• Applications requiring superior mechanical properties, reliability, and structural integrity

Delta Centrifugal® provides custom castings for demanding applications across various industries: 

• Oil & Gas: Bushings, sleeves, seal rings, and pressure-bearing parts
• Aerospace and Defense: Components requiring precise dimensional control, minimal porosity, and high strength.
• Power Generation: Pump and valve components, liners, and tubes for high-temperature environments
• Marine and Chemical: Corrosion-resistant parts such as housings and bushings
• Steel Mills: Rollers and bearing sleeves that demand toughness and durability

We cast parts in more than 200 alloy grades, including stainless steels, nickel-based alloys, duplex, cobalt alloys, and many specialized materials tailored specifically to your requirements. 

Why Choose Delta Centrifugal®? 

Choosing centrifugal castings over bar stock isn’t just about efficiency—it’s about partnering with a supplier who genuinely understands your needs and the challenges you face every day. 

At Delta, we: 

• Provide expert engineering consultation and support from concept through production 

• Cast components up to large diameters up to 30 inches on the OD, with precision accuracy 

• Offer extensive in-house capabilities: foundry operations, heat treatment, machining, and rigorous quality control (ISO 9001, PED, ITAR certified) 

• Maintain strong, collaborative relationships—our customers regularly turn to us to help solve material challenges, reduce costs, and shorten lead times. 

If you’re using bar stock today and want a clearer picture of how centrifugal casting might improve your parts, reduce costs, and streamline your process, let’s discuss it. Our technical team can evaluate your current part designs and help quantify exactly where and how centrifugal casting can benefit you. 

Ready to explore whether centrifugal casting makes sense for your next project? 

Call us directly: (254) 773-9055 | Email: sales@deltacentrifugal.com